Are Vertical Axis Wind Generator worth it?

[Muchachos]

Hi, 

I leave in the city and I am considering getting a wind generator to augment my solar capacity.

I ideally need a wind generator that would be installed on the roof and not make much noise.  The vertical axis wind generators seem to be the best fit for this. 

Looking around I found the ATLAS2.0 Wind Turbine 2KW.   ATLAS2.0 2000W Wind Turbine (Fully optimized for ground conditions)

Is there anyone using this wind generator or similar and what is your experience?

 

[Solarphile]

I was looking at the very same wind charger to supplement my solar system. I was doing a lot of research because I didn’t want to waste money on something that would essentially not work. I found this article (among others) and decided to rather just add more panels, as they are cheaper. Also panels have no moving parts. 
 

https://scoraigwind.co.uk/category/vertical-axis-wind-turbines-vawts/
 

However you can take a chance and see if it works for you. If it does, then I will buy one too...

[Muchachos]

[Muchachos]

This article does look a bit dated but the questions are valid. Will be great to see something not older than two years. Especially because of the many product available. Most of the Chinese brand have complains about not delivering nothing close to the power stated.

[Solarphile]

I thought that the wind charger in question was selling for a good price and comes with a charge controller for not much more. But after reading many posts about wind turbine problems I decided that panels are easy for me to install myself and I have enough capacity left on my three charge controllers to add many more panels. 

The thought of charging the batteries when the sun is down is very appealing to me as where I live can get very windy. However the normal horizontal axis turbines are noisy and that was why I looked at the vertical axis turbine. Unfortunately there are no online reviews on this model, and I don’t want to spend R15K to R20k to install one and then discover that it doesn’t perform as advertised. For that kind of money I can buy lots more panels... 

I would love to chat to someone who has this turbine and can give real evidence of how well it works. 

[Muchachos]

I have one charge controller and it is running at capacity. Adding more panels means adding a charge controller and a battery as well which is going to be more than spending the R20K to get this wind turbine.

It would be great to charge when there is no sun especially when it is raining and cloudy. 

The Tesup online marketing people claim that they will be setting up a local office soon. In that can case returning the generator if your are not happy with it will not mean paying for shipping to London which might be the price of the generator. 

Yeah, it would be nice to have get SA usage data on this turbine.

Are there no other locally made horizontal axis turbine? I have searched have not seen any yet?

[phil.g00]

1 hour ago, Muchachos said:

The Tesup online marketing people claim that they will be setting up a local office soon. In that can case returning the generator if your are not happy with it will not mean paying for shipping to London which might be the price of the generator. 

Some reviews here: https://ie.trustpilot.com/review/tesup.co.uk

Hugh Piggott of Scoraigwind literally wrote the book on small wind. I would not discount his views out of hand.

He thinks VAWT are toys. 

However, even with a great turbine you need wind, if you don't live in a really windy place you don't have it.

If you add vertical E-W panels, you can produce watts earlier and later in the day using the same charge controller. They wont produce energy at night, but it is still at a time when your present set up isn't generating.

Maybe not a lot more watts, but I'd wager many times more than that VAWT in a year.

Edited September 14, 2020 by phil.g00

[Muchachos]

6 hours ago, phil.g00 said:

If you add vertical E-W panels, you can produce watts earlier and later in the day using the same charge controller. They wont produce energy at night, but it is still at a time when your present set up isn't generating.

I have a 16x405W panels connected in 4x4 to a Victron SmartSolar Charger 250/100 which is currently peaking at 5200 kWh generation between 10:00 and 14:00. I have been told this is close to the limits of the charger rated at 5800W for 48V. 
 

Would adding vertical E-W not make the charger go over it’s limit?

What would my new configuration look like with these new panels, assuming I add 4 east and 4 west facing?

Also, what is the difference between my current default North facing installation and the vertical E-W installation?

How much power percentage wise should I expect on raining days?

[DeepBass9]

Just check if you have enough wind. There is no power to be harvested in a breeze, you need strong wind. Also in strong winds, wind generators can be noisy and your neighbours might not like it.

[Muchachos]

7 hours ago, phil.g00 said:

Some reviews here: https://ie.trustpilot.com/review/tesup.co.uk

Thanks, shocking.

[phil.g00]

24 minutes ago, Muchachos said:

Would adding vertical E-W not make the charger go over it’s limit?

Vertical panels wont add to your noon peak, think about it.

They will add to generation before 10:00 and after 14:00 though on a clear day.

A thumbsuck:

With an extra 1200W of vertical due East panels, I'd guess power would start at first light, maybe 500W within half an hour of dawn  YMMV.

24 minutes ago, Muchachos said:

How much power percentage wise should I expect on raining days?

Another thumbsuck:

On an overcast day they will contribute all day long at probably around 3% of rating with your North -facing panels at about 5% of rating.

So you are going to get very little from your panels when it is overcast. The best orientation for overcast days is perfectly flat at maybe 8% ish.

In a nutshell the more panels the better, you get something but not a lot.

The difference is if it's light you'll get something, with a wind turbine you get nothing below a certain wind speed.

Edited September 15, 2020 by phil.g00

[Muchachos]

5 minutes ago, DeepBass9 said:

Just check if you have enough wind. There is no power to be harvested in a breeze, you need strong wind. Also in strong winds, wind generators can be noisy and your neighbours might not like it.

My area is 3m/s average and close 7m/s on windy days. 

[DeepBass9]

Read this : https://en.wikipedia.org/wiki/Beaufort_scale

From my experience with a wind generator, you need Beaufort 4-5 or above to generate any power, so the wind must be bending the trees. Where I am that is just too intermittent to produce any noticable contribution to my power needs. In a city (which one) there is lots of interference from buildings, trees etc, so I doubt you will have much success with wind, unless you are in a really exposed position.

[DeepBass9]

26 minutes ago, Muchachos said:

My area is 3m/s average and close 7m/s on windy days. 

I think this answers your question. Wind power goes up with the square or cube of the wind speed, so at 3 or 7 m/s you will probably be producing nothing. If you can put your hand up to the wind and feel a push, then the wind has some power, otherwise not.

The specs on that generator are :

 

ATLAS2.0 2000W Wind Turbine (Fully optimized for ground conditions)

Rated Power @11.5 m/s= 1200 Watts

Rated Power @15 m/s= 2020 Watts

[Muchachos]

43 minutes ago, phil.g00 said:

With an extra 1200W of vertical due East panels, I'd guess power would start at first light, maybe 500W within half an hour of dawn  YMMV.

This sound like a good idea. How do I do this cost effectively? I do not want to buy more 405W Canadian Solar panels.

Do you go with many small panels or few big panels? Does it make a difference?

 

[phil.g00]

1 minute ago, Muchachos said:

Do you go with many small panels or few big panels? Does it make a difference?

You will need to add matching strings if you want to use the same controller.

[DeepBass9]

Sorry to labour this point, but : Rated Power @15 m/s= 2020 Watts occurs at Beaufort 7, which I doubt occurs very often in any location.

[Muchachos]

1 hour ago, DeepBass9 said:

Sorry to labour this point

Will take 500W in a raining and at night. I just need close to 800W to keep the lights on.

[Muchachos]

1 hour ago, phil.g00 said:

You will need to add matching strings if you want to use the same controller.

Sorry I'm only one month with solar. Can I can change my configuration to 6/8 in series?

Is there a limit to how many panel you can have in Series and in parallel?

Trying to get to the optimal configuration for around 500-1000W on a rainy day without a new charge controller.

[Muchachos]

1 hour ago, DeepBass9 said:

If you can put your hand up to the wind and feel a push, then the wind has some power, otherwise not.

Is there a wind monitor with a log that I can use go get actual wind speed for my house instead of the wind database?

[DeepBass9]

5 minutes ago, Muchachos said:

Is there a wind monitor with a log that I can use go get actual wind speed for my house instead of the wind database?

There are websites that give average wind speeds and wind potential. You just need to look up you area.

Bear in mind that the wind generally doesn't blow when you need it, as I've noticed. Like now until October is my best time for wind potential, except that the sky is clear and the solar works very well. When the wind gets up in the afternoon, the batteries are pretty much charged, so the controller brakes the turbine. In the evening it is generally still, so no power is produced. Sometimes when a cold front comes through with strong winds overnight, then it helps a bit, but otherwise not. 

We have a guest lodge, so the wing generator gives that 'off grid' type of vibe, but it is actually just a toy or conversation piece. It is not practical in any way. 

Rather get more solar panels or batteries, that will be much more useful, unless you stay somewhere with constant strong wind.

[phil.g00]

1 hour ago, Muchachos said:

Can I can change my configuration to 6/8 in series?

Is there a limit to how many panel you can have in Series and in parallel?

You cannot exceed the voltage rating of the MPPT, this is a hard limit. In your case I believe 4 panels in series will be the maximum length of string. 

Exceeding this voltage will damage the MPPT.

The number of strings is  a different story, this is the current output limit superimposed on you by the MPPT.

It is not a strictly a power limit but depends on your battery voltage. It might be known as a 48V system, but the charging voltage may be 10V higher. It is a current limit, in your case it is 100A.

If you added another North-facing string that peaked simultaneously with you existing panels you would experience "clipping". In other words you'd hit your ceiling output and the peak would be a flat line. Exceeding this limit shouldn't damage anything.

Indeed it may be worthwhile having a number of strings so that most of the year you don't clip, and only clip on great days.

I am a proponent of not having North-facing panels, and rather having E/W panels. This way I can get a lot more panels for the same noon peak. More panels are better when it is overcast.

Edited September 15, 2020 by phil.g00

[Muchachos]

4 hours ago, phil.g00 said:

You cannot exceed the voltage rating of the MPPT, this is a hard limit. In your case I believe 4 panels in series will be the maximum length of string. 

Exceeding this voltage will damage the MPPT.

This is the current utilisation on the solar charger. 

This is the PV generation pattern. 

Can I add 4x405W East Facing PVs and 4x405W West facing panels to this charge controller without having problems? 

 

[phil.g00]

From graphs I am going to go with a daily peak power from PV as 150V @35A, say a nominal peal power input of 5250 Watts. (In line with what you said).

I'll guess your charging voltage is say 55V and you have 100A at that voltage, so you are capable of handling a peak of 5500W'ish.

So you have around 250Watts of headroom in your present configuration. Which isn't much.

Essentially you can't add any panels (N or normal slope E/W)  that add to your noonday peak. You won't have problems, but you won't reap a whole lot of benefits either.

So your options to harvest more power in a day without buying a second controller are:

A) Add vertical or near vertical East-West arrays which won't contribute to the noon peak. (You could add many strings of 4 x 405W panels E/W if they were vertical).

B)Reconfigure your North facing array to just normal slope E/W arrays.

Then you could add about 30%-50% more panels and still stay below the peak of your controller. This just be using E/W panels at your available roof gradient (normal slope), without using vertical panels. (Although you could still add vertical as well on top of that). 

 

 

 

 

[Muchachos]

Phew!! This is a lot to digest.

As a start what is the difference between normal slope E/W and vertical or near vertical East-West arrays?

 

4 hours ago, phil.g00 said:

So you have around 250Watts of headroom in your present configuration. Which isn't much.

Can I add 1 Extra Panel to each the existing 4x405W String to max out the charge controller?

4 hours ago, phil.g00 said:

A) Add vertical or near vertical East-West arrays which won't contribute to the noon peak. (You could add many strings of 4 x 405W panels E/W if they were vertical).

This sounds like the easiest option. Is it safe to assume that if I get 4x405W E and 4x405W West I should expect an additional 700W for my 6-10am and 2-6pm window?

This would also mean an additional 700w*5% for overcast days? 

 

4 hours ago, phil.g00 said:

Then you could add about 30%-50% more panels and still stay below the peak of your controller. This just be using E/W panels at your available roof gradient (normal slope), without using vertical panels. (Although you could still add vertical as well on top of that). 

Will get back to this one when I understand the different between the different installations.